An Xda users has received the update and even he has Captured the OTA update . The system version is 220.21.28 and You can simply update it by Going to Settings > Software update .
The update Includes Android 5.1 Lollipop + Stagefright Fix . Along with it , the update also comes with new app updates and new Bug fixes .
For Those who had not received the 5.1 update can install it manually by Downloading the Update from - Here
via - xda